A unified finite volume framework for phase‐field simulations of an arbitrary number of fluid phases

Abstract

While the phase-field methodology is widely adopted for simulating two-phase flows, the simulation of an arbitrary number (N ≥ 2) of fluid phases at physical fidelity is non-trivial and requires special attention concerning mathematical modelling, numerical discretization, and solution algorithm. We present our most recent work with a focus on validation for multiple immiscible, incompressible, and isothermal phases, enhancing further our library for diffuse interface phase-field interface capturing methods in OpenFOAM (FOAMextend 4.0/4.1). The phase-field method is an energetic variational formulation based on the work of Cahn and Hilliard where the interface is composed of a physical diffuse layer resembling realistic interfaces. The evolution of the phases is then governed by the minimization of the free energy of the system.The accuracy of the method is demonstrated for a number of test problems, including a floating liquid lens, bubble rise in two stratified layers, and drop impact onto thin liquid film.

Numerical investigation of oil droplet detachment from wall surface by a microbubble using ternary phase‐field model

“…The setup and simulation conditions were essentially the same as those in the simulation by Zhang et al 60 It should be noted that several validation tests have been proposed for simulation models of ternary-phase flows. For more information on this, see a paper by Bagheri et al 74 However, this study must consider not only the interaction between the ternary fluids, but also the interaction of the ternary fluids with the wall. Therefore, the test we employ, proposed by At the start of the computation, the bubble and droplet wetted and spread on the wall, and eventually reached a steady state.…”